<?php

function msubstr($str, $start=0, $length, $url = ''){
    $charset = "utf-8";
    $suffix = true;
    if($url != ''){
        $link = '<a href="'.$url.'" style="color:#E8A65F;">了解更多</a>';
    }else{
        $link = '';
    }
    if(function_exists("mb_substr")){
        if ($suffix && strlen($str)>$length)
            return mb_substr($str, $start, $length, $charset)."...".$link;
        else
            return mb_substr($str, $start, $length, $charset);
    }
    elseif(function_exists('iconv_substr')) {
        if ($suffix && strlen($str)>$length)
            return iconv_substr($str,$start,$length,$charset)."...".$link;
        else
            return iconv_substr($str,$start,$length,$charset);
    }
    $re['utf-8']   = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf]{2}|[\xf0-\xff][\x80-\xbf]{3}/";
    $re['gb2312'] = "/[\x01-\x7f]|[\xb0-\xf7][\xa0-\xfe]/";
    $re['gbk']    = "/[\x01-\x7f]|[\x81-\xfe][\x40-\xfe]/";
    $re['big5']   = "/[\x01-\x7f]|[\x81-\xfe]([\x40-\x7e]|\xa1-\xfe])/";
    preg_match_all($re[$charset], $str, $match);
    $slice = join("",array_slice($match[0], $start, $length));
    if($suffix) return $slice."…";
    return $slice;
}

?>